NCERT Solutions for Ganita Prakash (Part 1) Chapter 6 Number Play
Updated on 2026-09-05
About this chapter
Numbers can carry information about an arrangement without telling you the actual values — each child calls out how many children ahead of them are taller. Parity means being even or odd. An even number can be arranged in pairs; an odd number always leaves one out. Parity rules: even + even = even, odd + odd = even, even + odd = odd. A sum of an odd count of odd numbers is odd; of an even count of odd numbers is even. The n th even number is 2n and the n th odd number is 2n – 1. In a 3 × 3 grid filled with 1 – 9, all row sums add to 45 and all column sums add to 45. A magic square from 1 – 9 has magic sum 15 and 5 at the centre. The Virahāṅka sequence 1, 2, 3, 5, 8, 13, 21, 34, 55, … was first written down in India around 700 CE while counting rhythms of short and long syllables. In a cryp
- Numbers Tell us Things
- Picking Parity
- Small Squares in Grids
- Parity of Expressions
- Some Explorations in Grids
- Generalising a 3 × 3 Magic Square
- The First-ever 4 × 4 Magic Square
- The Virahāṅka–Fibonacci Numbers
- Digits in Disguise
- –144Section 6.5 Digits in Disguise
Exercises
- In-text Questions — Numbers Tell us Things Page 127
- In-text Questions — Numbers Tell us Things Page 128
- Figure it Out — Numbers Tell us Things Page 128
- In-text Questions — Picking Parity Page 129
- In-text Questions — Picking Parity Page 130
- Figure it Out — Picking Parity Page 131
- Small Squares in Grids — In-text Questions Page 131
- Parity of Expressions — In-text Questions Page 132
- In-text Questions — Some Explorations in Grids Page 133
- In-text Questions — Some Explorations in Grids Page 134
- In-text Questions — Some Explorations in Grids Page 135
- In-text Questions — Some Explorations in Grids Page 136
- Figure it Out — Some Explorations in Grids Page 136
- Generalising a 3 × 3 Magic Square — Math Talk Page 137
- Generalising a 3 × 3 Magic Square — Figure it Out Page 137
- The First-ever 4 × 4 Magic Square — In-text Questions Page 137
- –141Section 6.4 Nature’s Favourite Sequence: The Virahāṅka–Fibonacci Numbers! — In-text Questions Page 140
- In-text Questions — The Virahāṅka–Fibonacci Numbers Page 142
- In-text Questions — Digits in Disguise Page 143
- –144Section 6.5 Digits in Disguise — Figure it Out Page 143